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1.
Acta Histochem ; 124(7): 151949, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36007436

RESUMO

Male infertility affects many couples around the world and can be related to environmental factors such as exposure to high temperatures. Even so, automated methods evaluating the seminiferous tubules to detect testicular damage are still scarce. In search of new approaches to automation in the microscopic analysis of the testis; the present study used the fractal dimension, lacunarity, multifractality and quantitative morphometry to quantify changes in microphotographs of the seminiferous lumen in testicles reversibly damaged by heat stress (43 °C, 12 min). The parameters fractal dimension, lacunarity, multifractality (Dq and α), perimeter, feret and circularity were able to detect changes in the seminiferous lumen at 7, 15 and 30 days after the testicular damage. These methods also detected the recovery of spermatogenesis at 60 days after heat stress. Area, f(α), centroid X and Y, roundness, rectangle height and width were unable to detect changes caused by heat stress. In conclusion, computer assisted methods applied to the seminiferous lumen images can be a useful new viewpoint to analyze microscopic changes in the testicles, a fast low-cost tool to assist in the automated quantification of testicular damage.


Assuntos
Fractais , Testículo , Resposta ao Choque Térmico , Humanos , Masculino , Túbulos Seminíferos , Espermatogênese
2.
Electromagn Biol Med ; 39(4): 403-410, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32954862

RESUMO

Animals developed or in an embryonic stage, are constantly subjected to magnetic pollution generated by electrical and electronic devices. Several researches have used the bird embryo as an experimental model to evaluate the action of magnetic field (MF) and electromagnetic field (EMF). This study proposed to perform a morphometric evaluation in the embryos and in the blood vascular network of the yolk sac membranes (YSM) of Japanese quail (Coturnix japonica) exposed to the 60 Hz MF with two different intensities (0.16 and 0.65 mT). A total of 30 eggs were used, 10 eggs were used for each assay. Each assay formed a group (control group, group submitted to the MF of 0.16 mT and 0.65 mT). The images of the skeletonized vascular network of YSM were evaluated by two methods of fractal dimension: box-counting dimension (Dbc) and information dimension (Dinf). The embryos were evaluated by body mass, percentage cephalic length and body area. The fractal dimensions revealed no difference among groups. There were no significant differences in relation to embryonic body mass among groups. However, the embryos exposed to 0.65 mT MF presented a smaller embryonic body development (body area and percentage cephalic length). In conclusion, 0.16 mT and 0.65 mT magnetic fields were not able to generate significant effects on vasculogenesis and angiogenesis. However, the embryos exposed to 6 h of magnetic field with 0.65 mT intensity and 60 Hz frequency showed a decrease in embryonic body development.


Assuntos
Vasos Sanguíneos , Coturnix/embriologia , Embrião não Mamífero/irrigação sanguínea , Campos Magnéticos , Animais , Vasos Sanguíneos/fisiologia , Tamanho Corporal , Embrião não Mamífero/embriologia , Fractais , Neovascularização Fisiológica , Fatores de Tempo
3.
HardwareX ; 8: e00132, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35498270

RESUMO

A major frontier in neuroscience is to find neural correlates of perception, learning, decision making, and a variety of other types of behavior. In the last decades, modern devices allow simultaneous recordings of different operant responses and the electrical activity of large neuronal populations. However, the commercially available instruments for studying operant conditioning are expensive, and the design of low-cost chambers has emerged as an appealing alternative to resource-limited laboratories engaged in animal behavior. In this article, we provide a full description of a platform that records the operant behavior and synchronizes it with the electrophysiological activity. The programming of this platform is open source, flexible, and adaptable to a wide range of operant conditioning tasks. We also show results of operant conditioning experiments with freely moving rats with simultaneous electrophysiological recordings.

4.
J Therm Biol ; 84: 1-7, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31466741

RESUMO

Heat can trigger testicular damage and impair fertility. Leydig cells produce testosterone in response to stimulation by luteinizing hormone (LH), which induces Ca2+ entry and K+ efflux through ion channels in their plasma membrane. Considering that mechanisms coordinating the Leydig cell responses to hyperthermic stress remain unclear; the present study analyzed the effects of heat stress (HS, 43°C, 15 min) and inhibition of Hsp90 on T-type calcium currents and voltage-dependent potassium currents (VKC) in mice Leydig cells. Results show that HS reduced the VKC steady state currents at +80 mV (45.3%) and maximum conductance (71.5%), as well as increased the activation time constant (31.7%) and the voltage for which half the channels are open (30%). Hsp90 inhibition did not change the VKC currents. T-type calcium currents were not affected by HS or Hsp90 inhibition. In conclusion, HS can slow the activation, reduce the currents and voltage dependence of the VKC, suggesting a possible role of these currents in the response to hyperthermic stress in Leydig cells.


Assuntos
Canais de Cálcio Tipo T/fisiologia , Proteínas de Choque Térmico HSP90/fisiologia , Resposta ao Choque Térmico/fisiologia , Células Intersticiais do Testículo/fisiologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Animais , Benzoquinonas/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Temperatura Alta , Lactamas Macrocíclicas/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Camundongos
5.
Microvasc Res ; 105: 114-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26873109

RESUMO

Like heparan sulfate proteoglycans, some monosaccharides and glycosaminoglycans, such as sulfated glucosamine (GS) and chondroitin (CS), integrate the vascular extracellular matrix and may influence vascular endothelial cell growth. To assess the effects of these substances on blood vessel formation, we used the chick yolk sac membrane (YSM) model and fractal geometry quantification, which provided an objective in vivo method for testing potential agents that promote vasculogenesis and angiogenesis. An image processing method was developed to evaluate YSM capillary vessels after they were implanted in a methylcellulose disk of GS or CS at a concentration between 0.001-0.1mg/disk (performed on 2-day old embryos). This method resulted in a binary image of the microvascular network (white vessels on a black background). Fractal box-counting (DBC) and information (DINF) dimensions were used to quantify the activity of GS and CS in vasculogenesis and angiogenesis. YSM treated with GS (0.001-0.1mg) and CS (0.03-0.1mg) showed an increase in fractal dimensions that corresponded to vitelline vessel growth compared to the control group (vehicle), with GS displaying higher fractal dimension values.


Assuntos
Indutores da Angiogênese/farmacologia , Sulfatos de Condroitina/farmacologia , Fractais , Glucosamina/farmacologia , Processamento de Imagem Assistida por Computador/métodos , Neovascularização Fisiológica/efeitos dos fármacos , Saco Vitelino/irrigação sanguínea , Animais , Embrião de Galinha , Relação Dose-Resposta a Droga
6.
J Appl Toxicol ; 32(3): 210-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21452164

RESUMO

The population exposure to electromagnetic fields (EMF) has been growing in recent decades. The generation, distribution and use of electric energy can generate low-frequency electromagnetic fields. The present study investigates the effects of EMF (60 Hz and 1 mT) on spermatogenesis of rats during different periods of maturation. Wistar rats were exposed to EMF from day 13 of gestation to postnatal day 21 or 90 in three daily applications of 30 min. Plasma testosterone concentration was not changed by EMF exposure; however, histopathological and histomorphometrical analyses of the testes showed testicular degeneration in a subset of animals exposed to EMF. The magnitude of the degenerative process varied between those individuals affected, indicating different individual sensitivity to EMF. The main alterations observed through transmission electron microscopy were highly electron-dense mitochondria with loss of their organization and cristae. Exposure to 60 Hz and 1 mT EMF can disturb spermatogenesis and may produce subfertility or infertility.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Testículo/efeitos da radiação , Animais , Diagnóstico por Computador , Masculino , Microscopia Eletrônica , Ratos , Ratos Wistar , Testículo/patologia , Testículo/ultraestrutura , Testosterona/sangue
7.
Int. j. morphol ; 24(1): 39-42, Mar. 2006. ilus
Artigo em Inglês | LILACS | ID: lil-626823

RESUMO

The vallates papillae lingual are located in the surface of the tongue in a area denominated of V lingual and it presents cells gustatory gathered in gustatory buttons. This research evaluated the height papilar in relation to the surface of the tongue of 519 lingual vallates papillae. 45 human tongue samples were selected, of both sexes, inside of the 40-50 year-old age group, obtained from necropsias accomplished in the Service of Verification of Deaths (S.V.O.) of UFPE/Secretaria of Health of the state of Pernambuco, in the city of Recife. The samples were classified different height levels accordingly in relation to the surface of the tongue, not establishing the exact height, where there was the predominance of the height above the lingual surface.


Las papilas valadas linguales están localizadas en la superficie dorsal de la lengua, en un área denominada V lingual y presentan células gustativas acumuladas en botones gustativos. Se evaluó la altura papilar en relación con la superficie de la lengua de 519 papilas valadas linguales. Fueron seleccionadas 45 lenguas humanas, de individuos de ambos sexos, de 45 a 50 años de edad, obtenidas de autopsias del Servicio de Verificación de Óbitos de la Universidade Federal ed Pernambuco /Secretaría de Salud del Estado de Pernambuco, Recife, Brasil. Las muestras fueron clasificadas de acuerdo a los niveles de altura en relación con la superficie de la lengua, no estableciéndose la altura exacta, donde hubo predominio de papilas ubicadas sobre la superficie lingual.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Língua/anatomia & histologia , Papilas Gustativas/anatomia & histologia , Brasil , Cadáver
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